The long-range objective of the proposed work in this application is to provide morphological information on the effects of metabolic hormones on liver. The techniques employed for the morphological analysis are cytochemistry, electron microscopy, and radioautography. We have chosen to concentrate on the action of glucocorticoids on hepatocytes, but effects of glucagon and insulin will be investigated as well. Since these hormones play a major role in regulating hepatic carbohydrate metabolism, we will give much attention to morphological and biochemical alterations in heaptic glycogen and glucose metabolism and changes in the subcellular organelles related to these processes. We have identified the smooth endoplasmic reticulum (SER) as one subcellular organelle important in glycogen metabolism which responds to the above hormones. Much of the work proposed in this application involves hormonal and metabolic experiments which are designed to alter hepatic metabolism in a known way allowing us to study changes in SER under these conditions. Moreover we will utilize cell fractionation techniques for isolating and "purifying" SER membranes allowing us to study various biochemical properties of these membranes from hepatocytes under different metabolic conditions. We propose to follow the incorporation of 3H-glucose into glycogen under metabolic conditions using techniques of light and electron microscopic radioautography. Finally, we will perform experiments with 3H-glucocorticoids and study the cellular and lobular localization of the hormone by radioautographic techniques.